Supplemental Resources

Supplemental resources and terms to be used together with DIFM’s Best Available Evidence Decision Tool. This is not an exhaustive list, but a compilation of resources recommended by experienced integrative and functional medicine RDNs.

Adhering to Ethical Standards

These apply to all RDNs in any area of practice. Approach all decision making within the context of ethical standards.

  1. Academy of Nutrition and Dietetics Code of Ethics for the Profession
  1. Academy of Nutrition and Dietetics Scope of Practice Decision Tool

Accessing Evidence-Based Information

The following links are selected resources to find evidence-based information on nutrition interventions. It is important to address the following topics with the patient or substitute decision maker involved in the shared-decision making process: informed consent; intervention risks, benefits, and uncertainties, potential outcomes, adverse events (side effects) and reporting; individual variability; subjective and objective monitoring and evaluation, specifically when, how, and why to initiate and discontinue intervention.

  1. Academy of Nutrition and Dietetics Evidence Analysis Library (EAL): andeal.org
    Check here for evidence-based nutrition practice guidelines and Academy published systematic reviews.

  2. Academy of Nutrition and Dietetics Nutrition Care Manual (NCM): nutritioncaremanual.org
    • Use the Nutrition Care section of the NCM to find research- and evidence-based nutrition care information for 150 diseases and conditions.
  3. Finding other evidence-based guidelines, recommendations, systematic reviews and primary research publications
    • PubMed ncbi.nlm.nih.gov/pubmed
      1. Find and access systematic reviews and primary research articles
    • Cochrane: cochrane.org and (for reviews) www.cochranelibrary.com
      1. Find and access evidence based guidelines and systematic reviews from other health professions organizations
    • UpToDate: uptodate.com
      1. A subscription database of reviewed medical literature and graded, evidence-based recommendations.
  1. National Institutes of Health (NIH), Office of Dietary Supplements (ODS):
    • Dietary Supplement Fact Sheets
    • Dietary Supplements: What You Need to Know
    • Dictionary of Dietary Supplement Terms 

Understanding and Communicating Scientific Research

It is important to help patients make informed decisions. When recommending any nutrition intervention disclosing the body of science on the topic/intervention, including positive, negative and neutral findings is important to effectively communicate scientific uncertainty with patients or substitute decision makers. This may also include an assessment and discussion on the potential impact of funding source on a study’s methodological quality, reported clinical outcomes, and author conclusions. Use the following resources for additional material on communicating scientific uncertainty and integrity.   

  1. Institute of Medicine (IOM). Characterizing and communicating uncertainty in the assessment of benefits and risks of pharmaceutical products: Workshop summary. Washington, DC: The National Academies Press.
  1. National Institutes of Health (NIH). Office of Disease Prevention (ODS). Communicating Possible Harms and Benefits of Treatment and Lifestyle. Webinar series.
  1. Understand and review the Academy’s commitment to scientific integrity and transparency in scientific activities including education for the public and professionals:

Best Available Decision Tool Terms and Definitions:

Term Definition
Adverse Event1 Any unintended medical occurrence associated with the use of a treatment or intervention in humans, whether or not considered intervention related.

Serious adverse event – an adverse event that results in death, a life-threatening experience, inpatient hospitalization, a persistent or significant disability or incapacity, or a congenital anomaly or birth defect; or requires, based on a reasonable medical judgment, a medical or surgical intervention to prevent an outcome described above.
Bias2 Systematic deviation from the underlying truth because of a feature of the design or conduct of a research study (for example, overestimation of a treatment effect because of a failure to randomize). Sometimes, authors label specific types of bias in a variety of contexts. Common types of bias: channeling, detection, interviewer, lead time, observer, recall, reporting.
Blind/Blinding2 (or Blinded or Masked) Patients, clinicians, data collectors, outcome adjudicators, or data analysts unaware of which patients have been assigned to the experimental or control group. In the case of diagnostic tests, those interpreting the test results are unaware of the result of the reference standard or vice versa.
Case control study3 A study which involves identifying patients who have the outcome of interest (cases) and matching them with individuals who have similar characteristics, but do not have the outcome of interest (controls), and then looking back to see if these two groups differed with regard to the exposure of interest (i.e., the hypothesized causal or contributing factors).
Case study or case series3 A descriptive study of one (case study or case report) or a series of patients (case series) defined by eligibility criteria, and where the unfolding course of events (disease progression, therapies, outcomes, etc.) is described in detail. The study researchers do not manipulate interventions. This study design is used to provide a detailed description of an uncommon disease or condition, a unique situation, or the introduction of a new technique.
Cohort Study3 A study that involves the identification of a group (cohort) of individuals with specific characteristics in common and follows them over time to gather data about exposure to factors and the development of the outcome of interest. Comparison groups can be defined at the beginning or created later using data from the study (e.g., age group, smokers/non-smokers, amount of a specific food group consumed).

Prospective cohort studies enroll individuals and then collect data at many intervals.

Retrospective cohort studies use an existing longitudinal data set to look back for a temporal relationship between exposure factors and outcome development. In the medical field, many studies labeled a “population-based clinical study” could be classified as retrospective cohort studies.
Cross-Sectional Study3 A study where exposure factors (e.g., individual or environmental risk factor, nutrition education) and outcomes (e.g., disease occurrence, eating behavior) are observed or measured at one point in time in a sample from the population of interest, usually by survey or interview. In this design, a researcher examines the association among factors and outcomes using a statistical test for association, but cannot infer cause and effect.
Evidence-Based Nutrition Practice Guidelines4 Evidence‐Based Nutrition Practice Guidelines are statements and treatment algorithms which are developed using the process of asking questions, systemically finding research evidence, and assessing its validity, applicability and importance to food and nutrition practice decisions. The guidelines are designed to assist the registered dietitian (RDN), RD/dietetic technician, registered (NDTR) team and other intended users and patient/client in making decisions about appropriate nutrition care for specific disease states or conditions in typical settings.
Evidence, Best Available Research4 The best available research/evidence refers to the most appropriate research/ evidence available to answer a question. Evidence‐ based guidelines and systematic reviews are considered the best available sources of research/ evidence. If these do not exist, then primary research is the best available and the type of question would determine the best research/evidence.

The four most common types of evidence analysis questions are: diagnosis, treatment, prognosis and etiology. The type of question you are trying to answer determines the best research design to seek.

For more information, visit the Academy of Nutrition and Dietetics Evidence Analysis Library at: www.andeal.org
Exposure/exposure status2 A condition to which patients are exposed (either a potentially harmful intervention or a potentially beneficial one) that may affect their health.
Health Outcomes2 All possible changes in health status that may occur for a defined population or that may be associated with exposure to an intervention. These include changes in the length and quality of life, major morbid events, and mortality.
Patient Reported Outcome Measure (PROM)5 Standardized, validated questionnaires that are completed by patients to measure perceived health status, functional status or health-related quality of life.
Patient-Important Outcomes2 Outcomes that patients value directly. This is in contrast to outcomes that clinicians may consider important. One way of thinking about patient important outcomes is that, were it to be the only that that changed, patients would be willing to undergo a treatment with associated risk, cost, or inconvenience. This would be true of treatments that ameliorated symptoms or prevented morbidity or mortality. It would not be true of treatments that lowered blood pressure, improved cardiac output, improved bone density, or the like, without improving the quality or increasing the length of life.
Primary studies2 Studies that collect original data. Primary studies are differentiated from synopses that summarize the results of individual primary studies and they are different from systematic reviews that summarize the results of a number of primary studies.
Randomized Controlled Trial (RCT)3 Individuals meeting eligibility requirements are randomly assigned into an experimental group or a control group. The experimental intervention (protocol, method or treatment) and its alternative(s) are clearly defined and their implementation is closely managed by the researcher.
Risk factors2 Risk factors are patient characteristics associated with the development of a disease in the first place.
Side effects6 Also known as adverse events, are unwanted or unexpected events or reactions to a treatment or intervention. Side effects can vary from minor problems like a runny nose to life-threatening events, such as an increased risk of a heart attack.

Generally, these are categorized as mild-to-moderately harmful or unpleasant, short-lived, and self-resolving, i.e., mild-to-moderate self-resolving gastrointestinal distress (nausea, gas, bloating, constipation, diarrhea, reflux), headache, or drowsiness. Side effects are often (but not always) potentially foreseeable, i.e., bloating or gas with change to a high fiber diet or initiating use of probiotics.
Systematic Review3 A summary of the scientific literature on a specific topic or question that uses explicit methods to conduct a comprehensive literature search and identify relevant studies, critically appraise the quality of each study, and summarize the body of literature or evidence to answer the question.

References

  1. United States Food and Drug Administration. Title 21 – Food and Drugs. In: Department of Health and Human Services, ed. Vol. 52010.
  2. Guyatt G, Rennie D, Meade MO, Cook DJ. User’s Guides to the Medical Literature: A Manual for Evidence-Based Clinical Practice. 2nd ed. New York, USA: The McGraw-Hill Companies, Inc.; 2008.
  3. Research and Strategic Business Development. Evidence Analysis Manual: Steps in the Academy Evidence Analysis Process. In: Academy of Nutrition and Dietetics: Evidence Analysis Library.; 2016.
  4. Quality Management Committee. Academy of Nutrition and Dietetics. Definition of Terms. 2017; 25. Available at. Accessed 8/4/17.
  5. Dawson J, Doll H, Fitzpatrick R, Jenkinson C, Carr AJ. The routine use of patient reported outcome measures in healthcare settings. BMJ. 2010;340:c186.
  6. United States Food and Drug Administration. Learning about Side Effects. 2017; https://www.fda.gov/drugs/resourcesforyou/consumers/ucm196029.htm. Accessed 9 Oct, 2017.